The following publications are believed to represent the current state of the art:    U.S. Pat. Nos. 4,310,437; 4,373,024; 4,507,546; 4,960,540; 5,108,655; 5,783,089; 5,827,453; 5,928,493; 6,207,722; 6,534,550; 6,616,845; 6,660,164; 6,689,271; 6,726,838; 6,960,304; 6,962,653; 7,001,519; 4,279,753; 6,110,389; 4,322,296; 4,620,929; 6,565,750; 3,506,125; 4,810,377; 5,080,793; 5,458,779; 4,188,289; 3,133,017; 1,790,975; 2,709,128; 5,779,886; 5,490,934; 6,726,838; 3,957,931; 4,179,366; 4,333,893; 4,385,988; 4,522,767; 4,537,731; 4,814,085; 4,814,125; 4,842,920; 4,985,182; 4,999,103; 5,168,058; 5,192,442; 5,200,081; 5,217,616; 5,429,740; 5,486,292; 5,543,039; 5,558,763; 5,783,066; 5,783,069; 5,871,674; 5,902,484; 5,948,262; 5,962,309; 5,980,738; 5,981,272; 5,985,148; 5,993,650; 6,015,497; 6,063,268; 6,077,424; 6,126,829; 6,136,194; 6,156,204; 6,210,578; 4,137,171; 4,045,344; 3,133,017; 4,394,268; 4,521,311; 5,554,289; 4,566,971; 4,820,415; 6,063,863; 4,839,053; 4,599,174; 4,231,863; 4,374,730; 5,030,353; 5,202,027; 5,698,094; 4,256,573; 4,454,038; 1,498,360; 7,261,811; 7,332,077; 3,788,477; 5,534,141; 5,736,047; 5,766,459; 6,572,774; 6,942,788 and 7,223,343, and    U.S. Published Patent Application Nos.: 2003/0087969 and 2004/0089592, and    Non-US Patent Nos.: DE 39 16 520; FR 2 707 183; ES 2 064 083; EP 0 575 314; EP 0 750 591 and EP 1 340 720;    PCT Patent Publication Nos.: WO 95/33695; WO 91/11396 and WO 95/25072, and
Other Publications:    “Biological treatment of highly foaming pharmaceutical wastewater by modified bubble-column under mechanical foam control”, K. Yamagiwa, M. Yoshida, A. Ohkawa and S. Takesono, Water Science & Technology, VoI 42 No 3-4, pp 331-337, IWA Publishing 2000;    “Performance characteristics of mechanical foam-breakers fitted to a stirred-tank reactor”, Takesono S., Onodera M., Yoshida M., Yamagiwa K., Ohkawa A., Journal of Chemical Technology & Biotechnology, Volume 78, Number 1, January 2003, pp. 48-55(8);    Database WPI Week 198730 Derwent Publications Ltd., London, GB; An 1987-209691, XP002381758 & JP 62 136296, 19 Jun. 1987, an abstract;    Database WPI Week 199901 Derwent Publications Ltd., London, GB; An 1999-003480, XP002381759 & JP10 277536, 20 Oct. 1998, an abstract, and Patent Abstracts of Japan Vol. 1996, no. 2, 29 Feb. 1996 & JP 07 275886, 24 Oct. 1995.